WASHINGTON – Pennsylvania is making progress to reduce pollution into the Chesapeake Bay watershed but is falling short of the pace needed to meet 2017 cleanup deadlines because of pesticide and other farm runoff, according to an analysis by an environmental group.

The assessment released Wednesday is based on an analysis of benchmarks that states in the watershed are aiming to meet to restore the bay. The study by the Chesapeake Bay Foundation and the Choose Clean Water Coalition found that Pennsylvania met or exceeded benchmarks in four areas to help reduce pollution from storm water and wastewater treatment plants. However, it fell short in four other areas to help limit agricultural runoff, including erosion and sediment control, soil conservation and forest buffers.

Pennsylvania is the largest contributor of nitrogen pollution to the watershed, caused in part by farmland fertilizers and pesticides that flow into streams after rainfall. The state now has roughly 19,000 miles of impaired streams. The report urges the state to pick up the pace in creating forest buffers as well as conservation plans to keep topsoil and nutrients on the land. It also calls on the federal government to hold states accountable so they will meet the deadlines.

“We are very concerned Pennsylvania will not meet its 2017 pollution reduction goals. The gap between what has been done and what needs to be done is substantial,” said Jennifer Quinn, an outreach coordinator for PennFuture, an environmental group based in Harrisburg, Pa. “Reducing water pollution benefits all citizens of the Commonwealth by protecting drinking water quality, improving aquatic habitat, and ensuring we have numerous places to fish and swim.”

In a statement, the Pennsylvania Department of Environmental Protection noted its continuing efforts to limit pollution in the bay, including updating nitrogen and phosphorous limits in permits for wastewater treatment plants and conducting 10,842 farm visits in the bay watershed since 2011.

“These initiatives, and others, will help Pennsylvania to work toward the 2017 milestone,” said spokeswoman Amanda Witman.

The multi-billion dollar restoration plan overseen by the Environmental Protection Agency involves six states within the 64,000 square mile watershed, urging them to reach 60 percent of their pollution-reduction goals by 2017 in hopes of achieving a full bay restoration by 2025.

As a whole, the study concludes that the states needed to do a better job of reducing agricultural as well as urban and suburban polluted runoff.

The progress report comes as farmers and 21 attorneys general are challenging the Obama administration’s plan to clean up the watershed. It is a reflection of political division over EPA’s authority to negotiate the 2010 agreement under the Clean Water Act.

Among the states that agreed to the Chesapeake plan, West Virginia is now opposing the cleanup, joining 20 other states which filed briefs against the EPA plan. Pennsylvania and New York are staying silent in the litigation, while Maryland, Delaware, Virginia and the District of Columbia signed briefs in support.

According to the EPA, farm runoff such as animal waste and fertilizer has created “dead zones” in the bay where nothing lives, taking a toll on the bay’s signature blue crab. About 17 million people live in the watershed corridor.

“Despite making progress, the Chesapeake Bay watershed still remains a system dangerously out of balance,” according to the analysis released Wednesday.